How to Use For Loop in PowerShell: Syntax and Examples

In PowerShell, use a for loop to repeat commands a set number of times by specifying an initializer, condition, and iterator inside parentheses. The loop runs while the condition is true, executing the code block inside { } each time.

Syntax

The for loop syntax in PowerShell has three parts inside parentheses separated by semicolons:

• Initializer: Sets the starting value of the loop variable.
• Condition: The loop runs while this is true.
• Iterator: Updates the loop variable each time.

The code to repeat goes inside curly braces { }.

powershell

for (<initializer>; <condition>; <iterator>) {
    # commands to repeat
}

Example

This example prints numbers 1 to 5 using a for loop. It shows how the loop variable $i starts at 1, runs while less than or equal to 5, and increases by 1 each time.

powershell

for ($i = 1; $i -le 5; $i++) {
    Write-Output "Number: $i"
}

Output

Number: 1
Number: 2
Number: 3
Number: 4
Number: 5

Common Pitfalls

Common mistakes include:

• Forgetting to update the loop variable, causing an infinite loop.
• Using incorrect comparison operators like == instead of PowerShell's -eq or -le.
• Placing the loop code outside the curly braces.

Here is a wrong and right example:

powershell

# Wrong: Infinite loop because iterator missing
for ($i = 1; $i -le 3;) {
    Write-Output $i
}

# Right: Iterator included
for ($i = 1; $i -le 3; $i++) {
    Write-Output $i
}

Output

1
2
3

Quick Reference

Part	Description	Example
Initializer	Sets start value	$i = 0
Condition	Loop runs while true	$i -lt 10
Iterator	Changes variable each loop	$i++ or $i += 2
Loop Body	Commands to repeat	Write-Output $i

Key Takeaways

Use for loops to repeat commands with a clear start, condition, and update.

Always update the loop variable to avoid infinite loops.

Use PowerShell comparison operators like -le and -lt inside the condition.

Put the repeated commands inside curly braces { }.

Test loops with small ranges to ensure they work as expected.